Given that cos x o = (frac{1}{r}), express tan x in terms of r

MATHEMATICSWAEC 2011

Given that cos xo = \(\frac{1}{r}\), express tan x in terms of r

  • A. \(\frac{1}{\sqrt{r}}\)
  • B. \(\sqrt{r}\)
  • C. \(\sqrt{r^2 + 1}\)
  • D. \(\sqrt{r^2 - 1}\)

Correct Answer: D. \(\sqrt{r^2 - 1}\)

Explanation

cos xo = \(\frac{1}{r}\); \(\sqrt{r^2 - 1}\)

By Pythagoras r2 = 12 + x2 - 1

x = \(\sqrt{r^2 - 1}\)

tan xo = \(\sqrt{r^2 - 1}\)

= \(\sqrt{r^2 - 1}\)

Back to WAEC 2011 QuestionsPrevious QuestionNext Question


Post an Explanation Or Report an Error

If you see any wrong question or answer, please leave a comment below and we'll take a look. If you doubt why the selected answer is correct or need additional more details? Please drop a comment or Contact us directly.

Your email address will not be published. Required fields are marked *

Don't want to keep filling in name and email whenever you make a contribution? Register or login to make contributing easier.